Electrical switch



Patented .lune ti, i943 UNlTED STATES rATENr ort-mg (Granted under theact oi March 3, i353, as

amended April. 30, 1923; 370 O. G. l?)

l@ Claims.

My invention relates to electrical switches, and in particular to thetype of switch which is constructed for use under water for controllingelectrical apparatus such as, for example, electric welding guns.

This application is a continuation-in-part of my application, Serial No.362,714, filed Cctober 25, llili, for Subaqueous end wending device.

a general object of my invention is to provide an improved electricalswitch which is suitable for manual operation under water.

Another object is to provide a switch adapted i'or undenwater operationin which the force of the water acting upon the switch contact operatingmember and tending to close the switch contact is counteracted by anopposing force set up in an opposite direction.

Another object of my invention is to provide e. switch which can beadjusted to compensate for water pressure acting upon the switch operating member so that the switch may be useful at various depths ofwater.

Another object is to provide a switch in which the operating memberthereof can be actuated with substantially the same manually appliedtorce irrespective of the distance which the switch may be located belowthe surface of the water.

A further object of my invention is to provide a switch adapted forunder-water operation which can be controlled automatically and remotelyby applying a pressure from an auxiliary source oi iiuid supply to theswitch contact operating member in such manner as to oppose the pressureof the water acting upon such member. The applied pressure is soregulated that when the force created thereby is greater than the forceof the water acting upon the contact operating member, the switchcontacts will be maintained open, but when such force is less than thatdue to the water pressure, the operating member will yield to 'the forceof the water and close the switch contacts.

A still further object is to provide an underwater switch which is socalibrated that the operator can quickly and accurately adjust thepressure compensation mechanism to balance the water pressure actingupon the switch operating member at the depth of water at which he maybe working.

These and other objects of my invention will become more apparent fromthe following detailed description, and from the accompanying drawing,in which:

Fig. 1 is a side view, partly in section, of a switch embodying myinvention;

Fig. 2 is a sectional side -view of a modified form of switch;

Fig. 3 is a view taken on lines 3 3 of Fis. 2c; and

Fig. 4 is a sectional side view ci another modication of a switchembodying my invention.

Referring now to Fig. l, my improved switch apparatus comprises a casingi which may be of any waterproof, electrically insulating material suchas bre, within which is carried the switch contacts. If desired, thesecontacts may be completely assembled in a separate casing i from which aplunger El extends, the latter being operable when depressed to closethe switch contacts. A suitable contact assembly is shown in U. S.Patent No. LQSGgG/u.

The housing l may be secured in position by inserting it between theside walls of a U-shaped clamping member Ei and securing it in suchposition by means of screws Ears are provided on the U member 6 andthese rest upon an internally shouldered portion of the casing I. The Umember 6 may be secured to the casing l by means of screws, which pass.through apertures in the ear portions of the member and thread into thecasing.

Resting upon the top' of the U member is a resilient body member 5 whichmay be made oi cellular rubber or any other suitable material.

A flexible diaphragm 2, which may also be made of rubber, is placed overthe resilient member 5 and is secured to the casing by means of a rigidplate member 3 which may be made of metal, if desired. This plate member3 includes an apertured portion within which a switch button 4 islocated. A stud portion of switch button 4 passes through an opening inthe flexible diaphragm 2 and is secured tightly within such opening by anut and washer. When button 4 is depressed the studded portion thereofpresses upon and moves the plunger 8 which operates to close thecontacts within the housing 1.

Leads I0 from the switch contacts may b e carried out of the casingthrough a stuiling box I I.

When the switch is immersed in water, the pressure of the -water (whichincreases with depth at the rate of approximately 62.5 lbs. per sq. ft.for each foot of depth) acting upon the exposed area of the flexiblediaphragm 2 will tend to move the diaphragm 2 and button l towards theplunger 8. Such movemet is opposed, however,V by the restoringiorce setup within the resilient body member 5 as the latter is compressed, whichprevents untimely actuation of plunger 8 by the button 4, therebypreable screws.

venting the .switch contacts from being moved to a closed position.

Cellular rubber may be obtained in varying degrees of resiliency. Hencethe particular type utilized for member will be so chosen that for agiven pressure of water (which will be determined by the distance belowthe surface of the water that the apparatus on which the switch isinstalled is intended to operate), it will prevent the button I fromtraveling a distance sumcient to abut the'plunger 8. The additionalforce necessary to'cause the button l to abut and depress plunger 3 canthen be supplied manually.

In Figs. 2 and 3, I have illustrated a modified form of switch which isadapted `to operate at depths greater than those at which a switch madein accordance with Fig. i can operate. The switch has a casing I2 whichmay be of the same material as the casing I. In this particularembodiment, the casing I2 is rectangular but it is obvious that it maybe of any suitable shape. Within the casing I2 is a rigid metallicsupport member 2| which has a central aperture cut therein and restsupon an internally shouldered portion of the casing and secured theretoby suit- A resilient body member I1 v.which is nonporous, such ascellular rubber, is provided with a central apertured portion and restsupon the support 2i. Member I1 is tlxed in position by a non-porousdiaphragm I3 of ilexible material such as rubber which is clamped at itsperiphery betweeny `a pair of rigid members I 4 and i6. These lattermembers, with the iiexible diaphragm I3 therebetween are secured to thecasing i2 by a bolt and nut at each corner thereof.

Amanually operable button I5 extends through a central opening indiaphragm I3 and is secured thereto by a nut I 9 which threads on theshank portion Il' of button I5.

A T-shaped contactor having a stem 20' is similarly secured through th'eapertured portion of a second ilexible diaphragm 22 by nut I9.

A pair of switch contacts 23-23 are fastened in position to inwardlyprojecting tongue portions 29 in the casing I2 by means of screws. Leads-25 soldered to lugs 24-24 are taken out through a stumng box 26.

It will be noted that the outer periphery of resilient member I1 isspaced from the internal wall of casing I2, thus leaving a chamber I1'which extends around the casing. This chamber connects with the exteriorof the casing I2 through a pipe 23 which threads into a threaded opening21 in the casing I2. To prevent seepage of Water or other fluid from thechamber I1 to the central opening in the resilient member I1, the topand bottom surfaces of the latter may be glued respectively to thediaphragm AI3 and disc 2 I.

If the pipe 23 is sealed, operation'of the switch is similar to that inFig. 1. The switch would be utilized in this manner when the waterpresand to thus increase the opposing force which this member presentsto resist depression of the ilexible diaphragm by the force of the wateracting downwardly thereon.

If the pressure in chamber I1' does not sufficiently oii'set thepressure of the fluid acting downwardly on diaphragm I 3, the pipe 2lmay be connected to a separate source of uid supply (not shown), andiluid pumped into the cham- -ber at the desired pressure. This fluid maybe liquid or gas, such as compressed air.

Manual operation is similar to that in Fig, l.

This type of construction permits the switch contacts 23.23 to also beoperated automatically, if desired, instead of manually.

To effect automatic operation, iiuid would be pumped into chamber I1'until the total force acting upwardly against the under side of thediaphragm I3 is greater than the total force exerted downwardly on theupper side of the diaphragm I3 by the water. This excess of force on theunder side of the diaphragm would be just suillcient to keep the shankportion I5' of button I5 out of engagement with the stem 2l'. When it isdesired to close the switch, a valve in the I uid supply line would beopened, whereupon the pressure due tol the fluid in chamber I1' would bereleased. Since the total force of the water acting downwardly upon thediaphragm would then be greater than the opposing force Y set up on theunder side of the diaphragm, the

diaphragm would then move downwardly, causing button shankA I5 to engagethe stem 20' of contacter 20 and move the latter until it bridges andcloses a circuit through contacts 23-23.

To open the circuit, fluid -would again be pumped into chamber I1' untilthe pressure was suilicient to cause contactor 20 to move upwardly andbreak its engagement with contacts 23-23.

In Fig. 4 I have provided another .type of construction whereby theforce of the water acting downwardly against the upper side of theilexible diaphragm may be balanced at any depth by a counterforce actingupwardly against the under side of said diaphragm.

In this modification the switch comprises a base plate 49 upon which acylindrical casing 3l f is mounted for rotation. A plurality of graphitesure acting upon the water exposed surface of plugs 4I are provided inorder that the casing may rotate easily upon the base plate 40, and astuillng box 33 together with a gland 39 prevents water from enteringthe interior oi the switch as the casing 30 is rotated.

An annular disc member 3B is provided with threads at the peripherythereof and these threads engage with complementary threads Il which areprovided on the insidewall of the' casing 30.

One or more guide members 31, which are fixedly secured to the baseplate l0, extend upwardly through aligned openings 49 provided in thedisc 33 and function to prevent the disc 39 from rotating with thecasing 39 as the latter is turned on base plate 40.

Since disc 36 cannot rotate, the interaction between the threads willcause it to move in translation upwardly or downwardly. depending uponthe direction in which the casing 39 is rotated.

'I'he top of the casing 30 is closed by a ilexible diaphragm member 3|and, if desired, an anthereby serves to stiifen the resilient membernular shaped rigid member 33 may also be provided to assist i:n'clamping the diaphragm 3| to the casing 30 to make it watertight. Acoiled asesora spring member it is seated upon an upturned portion ofthe disc 35 and is secured in position between the disc 36 and iiexiblediaphragm 3l.

A contactor 35 is secured to diaphragm 3| by nut 32 which serves as amanually operable switch button. Contactar 35 extends downwardly intothe body of the switch and terminates in an i. which is provided tobridge a pair of circular switch contact members 42 and 43 which aresupported, respectively, on cylindrical posts M3 and t?. Leads lllt4 maybe respectively connected to each contact member and are carried to theoutside of the switch through a stuffing box which may be provided inbase plate riti.

This type of switch operates in the following manner: When the switch istaken below the surface of the water, it is evident that a force due tothe pressure head of the water will act upon the flexible diaphragm 3|and tend to depress it. This torce can be counteracted, however, bytux/ninor the cylindrical casing 3i) on base plate it in such adirection as to cause the disc tit to move upwardly and compress thecoiled spring mi. The restoring force which is thus built up in thecoiled spring, due to its cornpression, will act upwardly against theunder ci the flexible diaphragm 3l and balance out the for-ce ofthewater on the opposite side of the diaphrag, v

have also provided indicator means wherethe operator of the switch mayadjust the compression on the coiled spring St below the suriace of thewater to suit the particlar depth which he is working. a plurality cilugs which are spaced around the periphery of the base plate lli), andan indicator arm which is attached to and rotates with the casingConsecutive lugs 5i may be marked with depth settings in any suitableintervals, such as, for example, 25 it., 50 it., 75 etc. i unable to seethe indicia on the lugs. operator, knowing the characteristics of theproper lug iii by tactile sense.

conclusion, while E have shown and described certain embodiments or myinvention, it 1 be apparent that changes and modifications be madetherein without departing from the spirit and scope oi my invention, asdefined in the appended claims.

For example, in some instances it may be desirable to replace thecellular rubber member in ig. 'l with a spring member such as membershown in Fig. t. Also, in some cases, it may be desirable to insert arigid disc member between the top oi the coil spring 34 and the flexiblediaphragm 3i in order to better distribute opposing force set up by thespring over the entire surface of the diaphragm.

As another example, it may be desired to substitute a coil spring suchas member 34 shown in Fig. 4 to replace resilient member l1 in Fig. Insuch case disc 2l is secured to causing l2 by a water-tight connectionand second flexible diaphragm 22 is made up with a water-tight joint todisc 2l.

Also, while I have described my invention in connection with its use asan under-water switch, it will be evident that it may be used equally asWell in other fluid mediums such as compressed air.

The invention described herein may be manuiactured and used by or forthe Government of Such means comprise the United States of america forgovernmental purposes without the payment ol' any' royalties thereon ortherefor. f

Having fully described my invention, claim:

In a switch adapted for use under iiaid presn sure` such as inunder-water operation, the com-1 bination comprising a switch casing,switch contact means, means for supporting contact means within saidcasing, a flexible diaphragm closure member for said casing, meansoperable upon a depression of said closure member.' to actuate saidcontact means, a support and a resilient pad member disposed between theunderside of said diaphragm closure member and said support, saidresilient member being be distorted upon depression of said ciosuremember whereby the restoring force created therein will be exertedoutwardly against said closure mem ber to oppose uuid pressure actingthereupon in an opposite direction.

2. In a switch adapted for use under fluid pressure such as inunder-water operation, the comclosure member for said casing, a movableswitch member operable upon a depression of said closure member tobridge said stationary contact members to close a circuit therethrough,a support plate, and a resilient pad member disposed between saidsupport plate and the underside of said diaphragm ciosure member, saidresilient member being adapted to be compressed upon depression of saidclosure member whereby the restoring force created therein will beexerted outwardly against said closure member to oppose uid pressureacting thereupon in an opposite direction.

3. .it switch adapted for use under fluid pressure such asin under-wateroperation comprising a easing, switch contact means disposed therein, aflexible diaphragm closure member for said casing, means operable upondepression of said diaphragm member to actuate said contact means, andmeans for admitting fluid under pressure to the interior of said casingto oppose fluid pressure acting upon the exterior ci said diaphragmmember.

In a switch adapted for use under :duid pressure such as in underwateroperation, the cornbination comprising a switch casing, a flexiblediaphragm ciosure member for said casing, a support plate, a non-porousresilient member disposed between said .support plate and the under sideof said closure member, said resilient member being spaced from theinner wall of said casing to form a chamber therebetween, means foradmitting uid under pressure to said chamber, switch contact means, andmeans operable upon adepression of said flexible diaphragm member toactuate said contact means.`

5. In a switch adapted for use under fluid pressure such as inunder-water operation, the combination comprising a base plate, a.cylindrical casing, the inner wall of which is threaded, means forsupporting said casing on said base plate for rotation thereon, a discmember, the periphery of which isthreaded for threaded engagement withthe threaded inner wall of said casing, an upstanding guide membersecured to said base plate, said guide member being extended through analigned opening in said disc whereby rotation of said casing upon saidbase plate will produce translatory motion of said disc, a exibledaphrasm. means securing said diaphragm to said cylindrical casingtoclose the latter, a resiiient member, said resilient member beingsupported between said diaphragm and said disc so that as said resilientmember is compressed by translatory motion o! said disc the restoringforce created therein will oppose fluid pressure acting upon saidilexible diaphragm.

7. In a switch adapted for use under fluid pressure such as inunder-water operation, the combination comprising a base plate, acylindrical casing, the inner wall of which is threaded, means forsupporting said casing on said base plate for rotation thereon, a disc,the periphery of which is threaded for threaded 'engagement with thethreaded inner wall oi' said casing, an upstanding guide member securedto said base plate, said guide member being extended through an alignedopening in said disc whereby rotation of said cas- 'ing upon said baseplate will produce translatory motion of said disc, a ilexiblediaphragm, means securing said diaphragm to said cylindrical casing toclose the latter, a spring, said spring being supported between saiddiaphragm and said disc so that as said spring is distorted bytranslatory ,motion of said disc the restoring force created thereinwill oppose iluid pressure acting upon said diaphragm, switch contactmeans, and means operable upon depression of said flexible diaphragm toactuate said contact means.

8. The 'combination in claim 'I and including indicator means associatedwith said casing whereby its position may be set to apply to said springmember the amount oi' distortion necessary to balance the fluid pressureacting upon said iiexible diaphragm.

9. In a switch adapted for use under :duid pressure such as inunder-water operation, the combination comprising a base plate, acylindrical casing, the inner wall of which is threaded, means forsupporting said casing on said. base plate for rotation thereon, anannular disc, the periphery oi which is threaded i'or threadedengagement with the threaded inner wall of said casing, an upstandingguide member secured to said base plate, said guide member beingextended through an aligned opening in saiddisc whereby rotation of saidcasing upon said base plate will produce translatory motion of saiddisc, a iiexible diaphragm, means securing said diaphragm to said casingto close thelatter, a coiled spring member, said spring being supportedbetween said diaphragm and said disc so that as said spring iscompressed by translatory motion of said disc the restoring forcecreated therein will `opose fluid pressure acting upon said diaphragm, apair oi' circular switch contact members, means for mounting saidcontact members concentrically on said base plate, and means operableupon depression of said diaphragm to bridge said contact members.

10. In a switch adapted for use under fluid pressure such as inunder-water operation, the

combination comprising a base plate, a cylindrical casing, means forsupporting said casing on said 'base plate for rotation thereon, a discmember disposed within said casing, means operable upon rotation of saidcasing to eiect translatory moe tion of said disc member, a flexiblediaphragm,

means securing said diaphragm to said casing to close the latter, aresilient member, said resilient member being supported between theunder side of said diaphragm and the upper side of said disc membersothat as said resilient member is compressed by translatory motion ofsaid disc member the restoring force created therein will oppose fluidpressure acting upon said diaphragm, switch `contact means, and meansoperable upon depression of said flexible diaphragm to actua saidcontact means.

JOHN D. CRECCA.I

